Can't get my audio interface to work with SONAR 3X. I get this error:
 

 
This interface is not listed in you hardware setup page.
Here is my config:
 

A couple of thoughts.
 
1.  Your latency settings seem to give you a little too much latency for proper recording without dropouts/crackles and such.  I would suggest you trim that ASIO Buffer Size from 192 to 128, which should bring your Total Roundtrip Latency down to around 10 milliseconds, which is a pretty reasonable balance.
 
2.  Is it possible that your default Windows audio device is also your audio interface?  If so, some Windows application (or Windows itself) may have gotten hold of your audio interface, and in ASIO mode only 1 application can be in control.
 
Bob Bone
 

1. I changed 192 to 128 and get same error.
 
2. No the windows default audio device is set to the PC's internal sound card which is different than this USB interface. Also the Kontrol Audio 6 control panel shows the number of clients connected to it. The number is shown as 0 clients before I launch SONAR. After I launch SONAR the number changes to 1 client.
 
BTW, the manual of this interface states that the driver supports multiple clients. In fact the Synthogy Ivory VSTI I use comes with a client which also uses ASIO and works together with the windows sounds in which case the control panel shows 2 clients. So the problem seems to be SONAR itself. It won't event work if it is the sole client while other VSTI hosts work fine even in multi client mode.

I am sorry if I inferred that the observation I made about your ASIO Buffer Size had anything to do with your error.  It does not, and is a completely separate issue.
 
I just happened to notice from your listed settings that your total roundtrip latency was up over 15 milliseconds, and latency that high produces an audible lag between playing a note and hearing it play back through Sonar while recording.  You want to try to keep your total roundtrip latency down to around or just under 10 milliseconds.  A sample rate of either 44.1 k or 48 k, record bit-depth of 24 bits, and an ASIO Buffer Size of 128 should get you down to somewhere between 9.3 and 10.5 milliseconds, and that should eliminate that audible 'lag' or any dropouts or crackles.
 
So, again, the above has nothing to do with the error you posted - it was just something else I happened to see.
 
Sorry for any confusion the above may have caused.
 
NOW, with regard to your reported issue:
 
1.  I found some info on the Cakewalk web site that was referencing the Unable to Open Audio Device error message you posted this thread about.  Here is that link:
 
https://www.cakewalk.com/Support/kb/reader.aspx/2003174
 
2.  Just curious - what is your Render Bit Depth set to?  (Edit>Preferences>File>Audio Data).  This defaults to 32-bit, and I have never changed it, but did see a post where someone got your same error message when they had it set to 64-bits, and it went away when they changed it back to 32-bits. 
 
3.  Is it possible that the audio interface is plugged into a different USB port than the one it was in during the driver installation?
 
Bob Bone
 

Hi Bort,
 
I have seen similar issues when opening projects that are not set to your device settings. IE... old project recorded at sample rates greater than your indicated 44k settings.  Does a new project open with the same error?

So I got it to work. The problem was that I was opening a project that had a recording with a higher sampling rate made previously with the internal card on my PC motherboard. I did that before I got this interface. This error is a bit too broad. They should make it more descriptive.
 
Although it works now, I get crackling during live piano play with Ivory VSTI and also lots of crackling when I move the volume sliders on any of the tracks or when I jump the play marker. My cheap internal Realtek sound card was cleaner than this it only buzzed every minute or so. This one crackles continuously.
 
Had to move the sample rate up to 96000 Hz and buffers to 192 for the cracking to go away. It's now gone during play but still there for the volume sliders and play marker moves. I am not impressed with this so called better audio interface.
 
Any other tricks I should try?
 
My "Record Bit Depth" is 16 and "Render Bit Depth" is 32. How do these relate to the "Audio Driver Bit Depth" which is at 24 and grayed out (can't be changed)? The transport display shows 96/16. Should these be different and why can't I change the "Audio Driver Bit Depth"?
 
Tried both "64 bit double precision engine" on and off. It makes no difference.

1.  It would have been helpful to know you were opening an existing project, rather than just trying to start Sonar.  The error message is accurate - a lack of information on what you were doing made it more difficult to nail down the cause.
 
2.  Your settings, or plugins, are what is causing the crackles you hear.  I suggest the following settings: Sample Rate (both Sonar and interface must match)  of either 44.1 k or 48 k, ASIO Buffer Size of 128, record bit-depth of 24 bits - try to get your Total Roundtrip Latency down to around 10 milliseconds or a tiny bit less.  Please note that these settings are reasonable for recording, but will you will need to bump up ASIO Buffer Size to possibly as much as 1024 when you begin mixing.
 
3.  I do not know why they have the grayed out bit-depth displayed, but in any case that is not where it gets set/changed.  To change the record bit-depth, go to Edit>Preferences>File>Audio Data, and you will see it there.
 
4.  As far as 'tricks to try', I would suggest you invest some time in reading the documentation, or working through some of the tutorials, buying one of the well-written books on Sonar, watching the numerous free videos, buying some of the pro videos, or at the very least hitting F1 to pull up context help documentation for whatever screen you have up and are struggling with.  You can either remain 'not impressed' with things, or you can educate yourself enough on the products you are using.  It's your choice.
 
Bob Bone
 
 
 

The driver bit depth is often grayed out. The driver bit depth is fixed. Since it is fixed at 24, this should not be a problem . As Bob points out, the record bit depth needs to be set elsewhere.

robert_e_bone
1.  It would have been helpful to know you were opening an existing project, rather than just trying to start Sonar.  The error message is accurate - a lack of information on what you were doing made it more difficult to nail down the cause.

 
Had I known that this could have even remotely been the cause, I would have mentioned it. I have a lot of experience building high performance gaming PCs but have never experienced a change of hardware render any software created project obsolete. I will keep this in mind going forward.
 

robert_e_bone
2.  Your settings, or plugins, are what is causing the crackles you hear.  I suggest the following settings: Sample Rate (both Sonar and interface must match)  of either 44.1 k or 48 k, ASIO Buffer Size of 128, record bit-depth of 24 bits - try to get your Total Roundtrip Latency down to around 10 milliseconds or a tiny bit less.  Please note that these settings are reasonable for recording, but will you will need to bump up ASIO Buffer Size to possibly as much as 1024 when you begin mixing.
 

 
I don't do any analog recording so my main focus is tuning for live play with MIDI backup tracks playing simultaneously. I tried 44.1k and 48k but I seem to get better latency at 96000Hz so I think its OK to stick with that. With this sample rate, anything below 192 ASIO buffer size gives me crackling during live play. At 192 I get clean live play with round trip latency of 6ms. However I can't get rid of the slight crackling and popping noises during bus volume slides and transport jumps no matter what setting rate or buffer sizes I use (I tried them all).
 

robert_e_bone
3.  I do not know why they have the grayed out bit-depth displayed, but in any case that is not where it gets set/changed.  To change the record bit-depth, go to Edit>Preferences>File>Audio Data, and you will see it there.

 
Since I only do MIDI recordings this should not matter for me right?
 

robert_e_bone
4.  As far as 'tricks to try', I would suggest you invest some time in reading the documentation, or working through some of the tutorials, buying one of the well-written books on Sonar, watching the numerous free videos, buying some of the pro videos, or at the very least hitting F1 to pull up context help documentation for whatever screen you have up and are struggling with.  You can either remain 'not impressed' with things, or you can educate yourself enough on the products you are using.  It's your choice.
 

 
I did most of that except buy the SONAR books. "Not impressed" was a little too strong. Was just surprised that the crappy sound card on my motherboard had no noise issues with bus volume slides using the ASIO4All driver unlike this better interface I got. Don't get me wrong it had other bigger problems.
 
 
 
 
 

Thank you for the detailed responses.  :)
 
OK - on the matter of the crackles and latency - it was not evident in your response that when you tried 44.1 k and 48 k that you did so while ALSO using an ASIO Buffer Size of 128 at the same time.  
 
I run with: Sample Rate = 48 k, record bit-depth of 24-bits, ASIO Buffer Size of 128, and I get a Total Roundtrip Latency of just under 10 milliseconds, AND more importantly - no dropouts/crackles/lag.
 
Since I did see from your content a test where you precisely matched my settings and then posted the Total Roundtrip Latency value on your system while running at those settings, I still politely ask you to run this exact test and then post back the precise results for that test, along with the Total Roundtrip Latency when running with these settings.  Please please please run this test.
 
I will look for your posted results from the above - and again, thanks for hanging in there :)
 
Bob Bone